Switching mechanism



2 Sheets-Sheet l R. F. MALLINA SWITCHING MECHANISM Filed July 12, 1941 Aug. 24, 1943.

TORNEV Aug. 24, 1943. R. F. MALLlNA 2,327,730

SWITCHING MECHANISM Filed July 12, 1941 2 Sheets-Sheet 2 //vvE/v TOR R. F MA LL/NA ATTORNEY Patented Aug. 24, 1943 SWITCHING MECHANISM Rudolph F. Mallina, Hastings on Hudson, N. Y.,

assignor to Bell Tele porated, New York, York phone Laboratories, Incor- N. Y., a corporation of New Application July 12, 1941, Serial No. 402,224

10 Claims.

This invention relates to switching mechanisms and particularly to improvements in switching mechanisms suitable for use in telephone or other communication systems.

An object is to simplify the operating characteristics and reduce the cost of switching mechanisms of the type in which a comparatively small number of automatically established electrical connections are desired.

Heretofore such small capacity switches have generally been of the so-called rotary type in which a set of wipers are rotated in stepsto establish connections with terminals in semicircular banks. Other types of switches have also been employed in which code bars are actuated in combination to select and establish electrical connection between sets of contacts. Such switches sometimes partake of the principles embodied in the well-known crossbar switches. One of my copending applications Serial No. 402,223, filed July 12, 1941, discloses a switching mechanism of this general type in which the operation of the code bars followed by the operation of a holding bar causes connections to be established by a selected set of contacts.

The present invention relates to a switch of this latter type and a feature thereof is an arrangement comprising a series of core bars in the shape of tapes arranged for movement longitudinally, a select bar in the shape of a tape located alongside of the code tapes and arranged to be moved longitudinally, a series of select fingers arranged across said two types of tapes normally engaging the select tape, aset of contact springs associated with each finger, a hold bar and a magnet for operating it. Said elements are so arranged that on the operation of a combination of code tapes slots in the code tapes are aligned for the subsequent entry therein of a particular corresponding select finger and on the operation of the select tape all of the fingers are released so that the said selected finger will enter me aligned slots to occupy a position Where the subsequent operation of the hold bar will actuate said finger to operate an associated set of contact springs.

A special feature is an arrangement whereby the hold bar locks the select tape in operated position and whereby the shape of the slots in the r.

select tape are such that, when the hold bar releases the select tape, the select finger released by the hold bar and all other fingers are returned by said slots to a normal position.

Another special feature is a locking arrange ment whereby the selected code tapes are locked in operated position and released when the hold bar is released.

The invention has been illustrated in the accompanying drawings in which:

Fig. 1 shows a top view of a mechanism in accordance with the applicants invention;

Fig. 2 is a front view of the switch shown in Fi 1;

Fig. 3 is a cross section taken on line 33 of Fig.

Figs. 4 and 5 are fragmentary views showing the relative positions and shapes of the slots in the code tapes and select tape in accordance with the applicants invention;

6 is a fragmentary front view of a portion of the mechanism relating to the locking of the select tape by the hold bar in accordance with the applicants invention; and,

Fig. 7 is a fragmentary perspective view of a set of contact springs and the mechanism for operating them in accordance with the applicants invention.

Referring now the drawings and particularly to Figs. 1, 2, 3 and 6. The mechanism is mounted on the mounting plate I and consists of the following parts. Four code bars or tapes marked 2 are mounted alongside of each other. Studs 3 and 4 secure a U-shaped frame member or bracket 5 to plate I. The code tapes are slidably mounted on studs 3 and 4 by means of screws 1 and 8 entering slots in the tapes so that the tapes may be shifted longitudinally from a normal position towards the right, as shown in Fig. l. The left-hand ends of these tapes are riveted to restoring springs l0 mounted on a bracket ll secured to plate I to hold the tapes in the normal position towards the left. The opposite ends of these tapes are connected respectively to armatures l2, l3, l4 and I5 controlled by magnets 16, ll, l8 and I9. These armatures and code tapes are held in normal position by the tension of springs I0 and the armatures have projections or backstops such as, for ex ample, 28 for armature l2 pressing against the plate I. The magnets are mounted on the usual return pole-pieces such as, for example, 22 for magnet i6. These pole-pieces have bent-over ears such as 23 for magnet l6 between which "re armature 12 for this magnet is mounted. Alongside the code tapes on the upper side looking at Fig. l is mounted a select tape 25 in the same manner as the code tapes except that it is held in normal position towards the right by a spring 28 secured to a bracket 21 mounted on plate I. The opposite end of the select tape 25 is secured to the armature 29 at 30 to be moved by this armature towards the left looking at Figs. 1 and 2. This armature 29 is mounted on a pin 3i which in turn is mounted between cars 32 extending from the return pole-piece 33 on which the magnet 34 is mounted so that when this magnet is energized, the armature 29 moves the tape 25 towards the left looking at Figs, 1, 2 and 6.

Alongside magnet 3d is mounted a hold magnet 39 on the return pole-piece Ml having ears 4! which serve as supporting bearings for a pinion $2 on which an armature i3 is mounted for this hold magnet 39. This armature is connected at Ml to a hold bar 35 which is located in front '1 the code tapes as shown in Fig. 1. Theholdbar is slidably mounted in the brackets ii and 38 secured to plate l for movement towardsthe left when the hold magnet 39 operates; The bold bar is U-shaped in cross section.

The locking mechanisms for maintaining the code tapes in actuated position and for releasing them when the hold bar is released are arranged as follows." The locking mechanism for each tape is identical. Referring to the locking mechanism'ffor' the tape controlled by magnet it, the pawl Eil thereof ismounted on a bracket 56 secured to plate i. When armature l2 operates, the notch 520'11 arm 53 of pawl 5| engages a projection 53 on armature it on the left-hand side thereof as thearm 53 is pressed downwardly by a spring 55.. Thus the armature i2, is held in operated position toholdthe associated tape in actuated position. It will be noted that the hold bar 15 is provided with a pawl 56 (for releasing armature t2) This pawl is normally tensioned by spring 5? to engage the armature l2 so that when the holdbar is moved towards the left, the pawl 5-5 is rotated on its pivots to raise the arm 59 thereof upwardly. The arm 59 normally engages a bevel surface on the arm 68 of pawl 5i so that when the hold bar 415 is,operated, the arm 55 will pass by this surface without interfering with the looking of armature I? by the pawl 55. Then when the hold bar 35 is returned to normal, the book 62 on arm 59 will engage the left-hand edge of the arm 60 and cause paw 1 5 i to be rotated back to normal posi tlon and thereby release oi unlocl; the armature l The li r e .tl. -h 1T ba 5 as tur tqnqr at, t e awl. llr e a e by. h arma ure i rit r rn t n rm l to au e h kv 6 free l fromi e ar 61 h e in he paw 5. t ret n t no malposition. The corresponding locking mecha nisms for the other tap'es will operate in the same manner w hires a M, aor a e s. a. .8 d, w; awrerat'e d to maintain the associated code tapes operated position untilthe hold bar {35 returns to normal when the locking mechanisms are operated t6 permit the release of the associated tapes.

It should be observed in connection with the select tape 25 and'th'e hold tar as and their operating magnets 33 and teas shown in Fig. 6 in particular that the armature 2'9 for the mag net 34 is' maintai'ned ih "ope'r'at'ed position by the aimatu'rp ls for the magnet by. means of a projection 55' 6"" armature '43 engaging a pro jection (ii an armature 29'; The purpose ofthis arrangement is to lock the select tape under control of the hold bar magnet and permit the magnet 3d to be deenergized to save operating current On the opposite side membersof the U-shaped member 5' are mounted rows ofsets ofselect springs; for example; the settle is one of the sets in the row on'th'e upper side and TB is one ofthe sets in the row on the lower side as shown in Fig. 2 Each of these 'setsof select spring'smay consist of three stationary springs T2 and three movable springs 73.- The movable springs 'iill are associated for making contact respectively with henever the associated armathe stationary springs 12 and are for this purpose connectedtogether by means of stud M which will be controlled by an operating spring 75 to establish the connections. This operating spring 15 is provided with a U-shaped member 16' which is located, as shown in Fig. '7 in particular,- t o extend downwardly for the set iii The U-shaped members for other groups in the upper rowextend downwardly in the same manher while the U-shaped members for the lower row extend upwardly. These U-shaped members are located slightly in front of the code tapes looking at Figs. 1 or '7. On the right-hand side of each U-shaped member 1'6 is located a select finger of the usual type consisting of a straight portion and: a coil portion,- the coil portion being connectedto the bottom member of the U-shaped member 5 Towards the right of each select finger 80 is mounted on the hold bar 45,,a member ,82 projecting on opposite sides of the holdbar 45. The upper end 83' of the member 82. is onthe right-hand side of the associated select finger llfl of the upper row and the lower projection Bilis located on the righthand side of the associated selectfinger 8d of the lower row. These select fingers, however, are normally locatd above the projections 33 for the upper row andbelow the projectionst l for the lower row sa as not to be a position to be operated; upon normally by the projection 83' or 84. Any oneof these select fingers, may, how

ever, elowered as will herein aftfer be described to pass in between the associated projections 83 or 84' andthe associated U-shaped member 16.

The various locations of the select fingers 8B are shown in connection with Figs, 4 and 5. In lg. 4 it will benoted that,with select tape 25 and the code tapes 2 in normal position, the 'se lect'iinger BO'rests against the left-hand edge of a slot 951'. This locates the select finger Gil slightly above the bottom surface 92 of the righthand portion 93 6f the slot 9! in the code tapes 2. slot 54 iii the Code tapes 2 lsshapd'tb'liave besides its right harid ortion as also a lefthand pjo'rtio'n 5wliich is dun cons derab y deeper nto the tape, while me not an in tli'elselelct tape 25 is shaped to have downwardly extending cari'is'hap'ed bottoin' surface 98. If one oririore of the code" tapes 2 are moved towards the right, slots 94 are aligned for the subsequent dropping or a fiiiger an int'o'the lower lefthand portitrls 95' or the shifted cone tapes. This is possible as it should be' o'bs'erved' that normal- 1y some of the code tape-s2 are; in positions so thattnis select finger 80 may be dropped down the slots of such tapes 'even though such tapes are not moved, that such tapesmay, for this p'urpose', be out for their entire width to the depth of the'portion' sfi if then the select tape 25 1s shifted towards the left; the select finger 8U opposite th'alig'ned slotsdwill, due to the downwardly slanting surface 536 in slot 90, be permitted to dropinto the deeper portion at of the aligned slot-s 9'4, and; come to-rest on the bottom surface 96 ofslot- In Fig. 5 a select finger 86 is shown dropped d'owriinto this deeper portion 956? slots 94' and resting on the surface 98-.

A description will-now be madeof a selective operation to select a particular set of contact springs such as 69,- lilor others in connection with Fig. 7'; The first operation that takes place will be the operation of a combination of magn'ets IE to I3, to shift the associated-code tapes towards the right. This will align slots 94 oppo-,

site a particular select finger 80 for the subse-. quent dropping of the finger 80 into the deeper portions 95 of these aligned slots 94 of the actuated code tape and into corresponding slots in code tapes that were not operated. If now the select tape 25 is moved toward the left, all the select fingers 80 will be released from the surfaces 9| and all but the selected finger 80 will now come to rest on the surfaces 92 of the associated slots 94. This single one of fingers 80 is, however, free to drop into the deeper portion 95 as determined by the combination of code tapes operated. This will place the selected select finger 80 opposite a projection such as 83 of a member 82 and between this projection and the associated U-shaped member 16. If now the hold bar 45 is operated towards the left, the projection 83 will engage the finger 80 and press it against the U-shaped member I6 and this member will I actuate the corresponding operating spring to act on the associated stud 14 to cause the associated movable springs 13 to engage the stationary springs 12, respectively, and thus close a desired connection.

As the armatures of the operated code tape magnets IE to l9 are locked by the pawls 5|, these magnets may be deenergized at this time and when the holding bar has come to rest in its operated position the select magnet 34 may also be deenergized as the select tape is held in operated position, due to the armature 43 of the holding magnet 39 looking thev armature 29 of the select tape. Therefore during the maintenance of this established connection, the only magnet that is continously energized is the hold magnet 39.

When the desired connection is ready for release, all that remains to be done is to deenergize the magnet 39 for the hold bar to release the armature 43 which causes the release of the armature 29 whch in turn causes the return of the select tape 25 to normal. It should be noted that on the return of tape 25 to normal, that is, when it is moved towards the right, the finger 80 will, of course, as soon as it has been released by the return of the hold bar, be lifted up out of the lower left-hand portions 95 of the associated slots in the code tapes by riding on the upwardly slanting surface 96 of the slot90 in the select tape and come to rest on thesurface 9| against the left-hand side of this slot 90. The return of the select tape to normal will, of course, also at this time reengage all the other select fingers 80, that is, these fingers will be lifted from engagement with the bottom surfaces 92 of the righthand positions 93 of the corresponding slots 94 in the code tapes and come to rest on the surfaces 9| of the slots 90 in the select tape. The return of the hold bar 45 to normal will now cause the locking mechanisms for the actuated code tapes to function to release these tapes for return to normal by having the hooks 62 on pawls 56 engage the left-hand edges of arms and restore the pawls 5| back to normal and thereby release the engaged armatures by lifting the arms 53 to free the projections 54 and while the armatures are releasing they will move the pawls 56 to release the pawls 5| to normal,

It should be noted that at the position 99 looking at Fig. 2, a special group of contact springs are provided, one pair of these contact springs I00 being associated with the lower projection |0| ofthe first member 82 so that when the hold bar is operated towards the left, these contact springs I00 are separated. These contact springs I00 may be used for any purpose such as for example to open the energizing circuit for the magnet 34 controlling the select tape. Another set of contact springs I02 is shown. One of these contact springs extends into slots in the code tapes so that when any of the code tapes are operated towards the right, these contact springs will be closed. These contact springs may be termed off-normal contacts and used for any purpose desired such as closing the circuit for the select magnet. A similar set of contacts I03 may be arranged with one of them engaging a slot in the select tape 25 so that when the select tape is operated towards the left, a connection between these two contacts is made. These may also be off-normal contacts and used for any desired purpose such as closing the circuit for the hold magnet.

What is claimed is:

1. In a switching device, a select bar, a plurality of code bars having slots therein, a series of select fingers tensioned only against said select bar, a set of contacts associated with each finger, means for shifting said select bar, means for shifting said code bars, the slots in said code bars being so arranged that the shifting of any combination of said bars aligns the slots for the subsequent free entry therein of a corresponding finger and the select bar being so shaped that on the subsequent shifting thereof, the selected finger is released and enters into the aligned slots, and means thereafter operative through the medium of said finger for causing the actuation of the associated contacts.

2. In a switching device, a select bar, a plurality of code bars having slots therein, a series of select fingers tensioned only against said select bar, a set of contacts associated with each finger, means for shifting said select bar, mean for shifting said core bars, the slots in said code bars being soarranged that the shifting of any combination of said bars aligns the slots for the subsequent free entry therein of a corresponding finger and the select bar being so shaped that on the subsequent shifting thereof this selected finger is released and enters into the aligned slots, and means for causing said finger to actuate the associated contacts, said select bar being further so shaped that on the release of said finger by said last-mentioned means and on the release of the select bar to normal said finger is restored to normal.

3. In a switching device, a select bar in the shape of a tape having slots therein, a plurality of code bars in the shape of tapes having slots therein, a series of select fingers located across all of said tapes and tensioned only against the select tape, a set of contacts associated with each finger, means cooperating with said tapes and fingers for shifting any combination of code tapes so that slots in said code tapes are aligned for the subsequent entry therein of a corresponding finger and for shifting said select tape so that a slot in said select tape permits the selected finger to enter into the aligned slots in the code tapes, and means thereafter operative through the medium of said finger to actuate the corresponding set of contacts.

4. In a switching device, a select bar in the shape of a tape having slots therein, a plurality of code bars, in the shape of tapes having slots therein, a series of select fingers located across all of said tapes and tensioned only against said select tape, aset of contacts associated with each finger; means cooperating with said ta es and fingers for shifting any corrloination of codetapes that slots in said co'deta'pes are aligned for the subsequent entry therein oi a 'correspoiiding finger-and for shifting said select tape so that a slot in said select ta e is aligned witiithe aligned slots in the code tapes to perhiit the selected finger to drop into said aligned slots; means then o erative for causing said fingerto actuate thecorres onding set or contacts; said s1ots in said" select tape'b'eiiig' furthe'r'so shaped that on the" release of the fing'er by said last mentiohedrheans and on the release; of the select tape the selected finger is returned to normal position. I

5-. In a switching deVice;-a select bar in the shape of a tape having slots therein; a plurality of code bars in the shape of tapes'lraving' slots therein, magnets for actuating said two" types of tapes longitudinally, a series or select fingerslocated across all of said tapes and tensibned only against said selecttape, a set of contacts assoch ated with each select finger, said select fingers and said slots being so located that on the longi: tudinal movement of any combination of code tapes, slots. are aligned for the subsequent entry therein of a corresponding finger and so that on the longitudinal movement; of said select tape a slot is shifted to permit the selected finger to enter therein and into the aligned slots in" the code tapes, a hold bar, a magnet for operating said hold bar, said hold barbeing arranged and associated with the selected finger when said hold bar is actuated to operate a corresponding set of contacts. l l

v6. In a switching device; a select bar; a plurality of code bars, a series of select fingers, ,a set of contacts associated with each finger; a holdbar, means forshifting any combination or code bars, means forshifting said select bar, means for shifting the hold bar, means controlled by the shifting of the select bar and any combi-' nation of code bars forlocking the shiftedcode, bars in actuated position and causing 8.001116 sponding finger to be selected, and means con: trolled by said selected finger and the shifting of the holdqbar for actuating the set of contacts associated with; said selected finger, and" means controlled by the release of the select bar and the hold bar for unlocking said code bars to release them and to restore the selectedfinger to normal.

7, In a switching device, aselect bar, a" plurality of code bars,. a;ser ies ofselect fingers; a set of contacts associated with each finger, a hold bar, means for shifting any combination of code MK 11 E33 9 shittin ,5 iSl... %Xi me es f r ites e q abe m s e s i eq by s iin t bald b r ac in l sefi bar in shifted: position, means control by the shifting or any combinatidn or co e bars for l'o li irig the shi fted co'de bars in actiiate'dpdsit means controlled by the shiftingfdf v hesjelec bar and any combination of co e bars'fo'r selecting a corresponding r nger, iii'a s coiitro ieiijtysald select niiger and the shifting of the old ar for actuating t eet or cont a I with said selected finger; and means con r0 by the release of said hold bar for relasing the select bar and for unlocking saidjcj'ode'" bars to release them and to-restor'e' the selected finger to h0rma1'., I v

8. In a switching device,- a selec'tb ar in" the shape ofa t "pe, a plurality ofcode" barsth shape oftape's; a series orselect fingfs}a set or contacts associated with each finger; a hold bar,- means'for' shifting any combination of code bars, means for. shifting said select tape, means for 1 shifting .sa-id' hold bar, means controlled hy'the shifting of the" select tape, any combination" of code tapes and the hold bar for looking the sele'cttape and'the shifted c'ode tapes in a'ctdated position andcausing a corresponding finger to be selected, means controlled by the selected finger and the shifting of the hold bar for actuating the'set of contacts associated with said selectedfinger, and means controlled by the release of the hold bar for unlocking said select tap'e'andsaid code tapes to release them and to restore theselected finger to normal.

9. In a switching device, a select bar in the shape of a tape having slots therein, a plurality of code bars in the shape of tapes haying slots therein, a magnet for actuating each of said two typeset tapes longitudinally, a' series of select fil'lgers located across all of s'aid'tape's', a setof con tacts associated with each select finger, said select fingers" and said slots being so located that on the longitudinal movement of any combination or said code tapes slots in the code tapes are aligned for the subsequent entry therein of a corresponding finger and on: thefllongitudinal niove'rnent dfthe's'elect tape, all fingers are rel'eel'sed so'that said corresponding finger will enter into the aligned slots in the code' ta es, a pawl associated-with each code tape to lock said code ta e in actuated: position when said code tape is-in'oved longitudinally, a hold bar, a magnet for operating said hold bar longitudinally, said hold bar being arranged and associated with the selected finger to operate a corresponding set of contacts when said hold bar is moved longitudinally, sai slots" in and select tape being so shaped that on the release of the selected finger by the hold bar and on the subsequent release of the" select ta e all" of said fingers will be actuated upon by inclined surfaces in said slots in the select tape toreturn to' normal position and pawl-s associated with said hold bar operating on the pawls associated with the selected code ta es torelea se said tapes from their locked position for return to normal ositions; 7

lo: In a; switchingdevice, a select b'ar having slots therein, a plurality of code bars having slots therein, a series of select fingers, am of con tacts associated with each finger, a hold bar, magnets for shifting said select bar and each of saidcode' bars and 's'aidhold bar, a awl associ' ated With each code bar for looking it in its shift ed position, said fingers and said select bar' and code' b'ars""b'eiiig so arran ed in" relation to each other that on the Shifting of any combination of code this slots in the code bars are aligned for the subsequent entry therein of aparticular co'rresptin'ding one of-sa'id fingers and on the shifting of the select bar all of the fingers are freed so that the said particular selected fingerwill enter tr'le aligned slots in the code bars and ina'sl'ot in the select" bar, means operative oh the subse qiie'rit shifting-of the hold bar for causing it to cooperate with the selected finger to actuate the associated set of contacts, and a pawl on aid hold bar for each code' bar operative to actuate the pawls ofsaid shifted code bars to unlock said code bar's on the release of said hold bar, said slots in the selectbar being so shaped that on ubsequent release of the select bar to normal all or the fingers are restored to norrna1 positions.

RUDOLPH F. MALLINAl 

